Conventionally, this type of substrate treating apparatus includes a treating section and an interface section. The treating section coats the substrates with resist film, and develops the substrates. The interface section transfers the substrates to and from the exposing machine acting as external apparatus. This substrate treating apparatus operates as follows, for example. The treating section first coats the substrates with resist film, and sends the substrates to the interface section. The interface section sends the substrates received from the treating section to the exposing machine. The exposing machine exposes the substrates. The interface section receives the exposed substrates from the exposing machine and returns the substrates to the treating section. The treating section develops the exposed substrates.
The construction of the interface section is disclosed in detail in Japanese Unexamined Patent Publication No. 2010-219434, for example. According to this publication, the interface section has three transport mechanisms. The first transport mechanism receives the substrates from the treating section, and passes the substrates to the second transport mechanism. The second transport mechanism receives the substrates from the first transport mechanism, passes the substrates to the exposing machine, receives the exposed substrates from the exposing machine, and passes the exposed substrates to the third transport mechanism. The third transport mechanism receives the substrates from the second transport mechanism, and passes the substrates to the treating section.
However, the conventional example with such construction has the following problem. With the conventional apparatus, a stoppage of at least one of the first and second transport mechanisms will delay the substrate transport between the interface section and the treating section.